Scott Williams said:
I just noticed a few days ago that the compass in the overhead info console on my '99 XJ has gone a little screwy. In the past it has always seemed pretty correct, but in the last few days it is showing about 1/8 direction off (shows W when it should say SW). Any ideas?
I seem to remember something about calibrating it somewhere. If I remember correctly you might have to do it each time you disconnect the battery. Never mind, I just looked it up in section 8V, you probably need to degauss the forward mounting screws and the roof panel. The part number for the degaussing tool is 6029, no idea how much they cost, I used to make my own years ago out of a coathanger and transformer. From the manual it looks like it would take about 10 min the first time you do it.
However there is also a calibration procedure for this compass, you are in wilmington NC and the compass variation number for that area according to their map is either zone 9 or 10, turn the ignition switch to ON, depress and releas the step button until you reach the compass/temp display. Depress and hold both the step and us/metric buttons down until 'var' appears in the display, takes about 5 seconds. Release both buttons, the current variance number will appear press and release the us/metric buttons to step thru the numbers untill your zone appears. Press the step button to set the zone into memory. Do it in a big empty field with no other metal buildings around and not under any powerlines...
For calibration [the above set the zone and did not calibrate it] start the engine in this big field, if the compass is still off calibration momentarily press and release the step button, press and release the us/metric buttons till cal appears, takes about 10 seconds the book says, and about 5 seconds later 'var' appears, release both buttons. drive the vehicle on a level surface away from large metal objects thru three or more complete circles in not less than 48 seconds. The CAL message will disappear from the display to indicate that the compass is now calibrated. SHeesh, sound as bad as setting up the gyros on the old FIST V fire support track...only faster....
Interesting note, mag antenna mounts on the roof of a compass equipped XJ are a NO NO, makes sense...
